Finger holder



Dec. 17, 1935. c. Q. GAREY 2,024,159

FINGER HOLDER Filed Oct. 21,1933 2 Sheets-Sheet '1' C. Q. GAREY FINGER HOLDER ZADMJiSQ Deal'Y, 1935.

Filed Oct. 21, 1933 2 Sheets-Sheet 2 Patented Dec. 1 7, 1935 UNITED STATES FINGER HOLDER Charles Q. Garey, Cleveland, Ohio, assignor to The National Acme Company, Cleveland, Ohio,

a corporation of Ohio Application October 21,

9 Claims.

This invention relates to finger holders for revolving spindles adapted preferably to operate in conjunction with .automatically operative chucks or collets, an object of the invention being to provide improved mechanism of this general character particularly designed for use in metal working machines, such as single and multiple automatic screw machines and in which the fingers are operated in one direction by centrifugal force thereby doing away with mechanical means including springs for this purpose and operative in the opposite direction by cam mechanism, the cam mechanism being operative in the form shown to close the collet on the work or stock rod while the release thereof is obtained by centrifugal action, with the result that a quicker opening of the collet or chuck is obtained as well as increased spindle speed. a

A further object of the invention is the provision of an improved mechanism of this character which will be simple and compact, efficient and effective in operation, and economical to manufacture, and will eliminate entirely the use of springs or other mechanical means for operating the fingers to spread the same, it being well-known that springs not only break but .due to continuous use lose considerable resiliency and therefore lose their effectiveness.

In the drawings accompanying and forming a part of this specification- Fig. 1 is a longitudinal sectional view of the improvement with the fingers in closed position;

Fig. 2 is a left hand end view thereof partly in section;

Fig. 3 is a cross sectional view thereof taken on line 3-3 of Fig. 1;

Fig. 4 is a side elevation partly in section;

Fig. 5 is a longitudinal sectional View similar to Fig. 1 illustrating the fingers in open position to release the work;

Fig. 6 is a detail perspective view of the back of the plate or collar;

Fig. 7 is a detail perspective view of the body; and

Fig. 8 is a detail perspective view of one of the fingers and its wedge or cam operating means.

Similar characters of reference indicate corresponding parts in the several views.

Before explaining in .detail the present improvement and mode of operation thereof, I desire to have it understood that the invention is not limited to the details of construction and arrangement of parts which are illustrated in the accompanying drawings since the invention is capable of other embodiments, and that the 1933, Serial No. 694,555

phraseology which I employ is for the purpose of description and not of limitation.

Heretofore in finger holders it has been desirable to use some mechanical means such as springs with all their disadvantages to operate or open the fingers but these springs limited the 5 spindle speed of the work spindle and retarded the opening of the collet or chuck and it was not practical in the small space provided to put the required number of springs thereby to increase the eificiency of the mechanism. 10

In the present improvement, these springs are entirely eliminated and centrifugal force is used to quickly throw out the fingers at the desired time. The elimination of the springs with all 5 of their disadvantages permits the rotation of the work spindle at unlimited speed without affecting the chucking mechanism. 'Besides this, the whole chucking means is entirely covered and makes a stronger and more substantial unit.

As is well-known, when applied to a multiple spindle machine, these finger holders are located each on the rear end of a rotating spindle, such as 26, carried by the indexable work carrier or cylinder. 25

The present improvement comprises a body 2 secured to the rear end of the usual work or stock rod rotating spindle 2B and this body has therein at one end a pair of oppositely disposed longitudinally milled slots 3 for the reception of a pair 30 of slid-able wedges or cams 6 each having a tapered camming face 5. These cams each have a transverse recess 6 for the reception of a longitudinally slidable sleeve 1 having an annular recess 8 for the reception of a shoe (not shown). 35 This shoe automatically shifts the sleeve 1 longitudinally in either direction by means of cams on a cam drum common in all automatic machines, such as the well-known National Acme- Gridley machine, to chuck and unchuck the stock. This sleeve 1 longitudinally slides the cams l along the body portion 2 in the longitudinal slots 3. The cams also fit into longitudinal slots (see Fig. 3) of the sleeve 1 and thus key the latter to the body for rotation therewith.

'At the other end of the body 2 is a second pair of oppositely disposed longitudinal slots 9 aligned with the slots 3 but somewhat deeper for the reception of the operating levers or fingers I0 pivotally supported in the slots 9 by pins H located at right angles to the slots 9. The sleeve 1 has an extended portion I2 overlapping the free ends of the fingers it to prevent them from being thrown out too far by centrifugal force when released by the cams. This extension also serves 5.5

to enclose the fingers and thus to prevent injury thereto.

The fingers 18 are so located as to be externally engaged by the cams and thus be wedged or forced down by the cams 4 and are provided at their opposite ends with thrust portions I3 in position to engage a plate 4 secured to the chucking tube 26 within the rotating spindle 28.

This plate M has a wide slot or recess I5 milled across the center forming projecting sides l5 extending over the body which is rabetted as at I 6, so that the tongued end of the body 2 fits within the slot E5 of the plate !4 and guides the same. These milled sides l5 are at right angles to the pivot pins I! and so overlap the ends of and lock the pins H in place. Thus the plate l4 rotates with the body 2 but is so located on a flanged collar M carried by the chuck tube or sleeve 2| and fitting into the end of the body 2 as to have a slight endwise motion due to the thrust of the fingers Ill.

Located at the one end of, the body 2 is an internal thread H by which the body is locked to the hollow spindle 20. This threaded end also serves as a nut to hold the gear in place on the spindle for rotating it. The body is also looked on the spindle 29 by two thread clamping screws l9 (see Fig. 2).

In the rear of the plate I4 is a nut 22 threaded to the chuck or collet carrying tube 2| and secured to the plate M by means of screw dowel pins 23 which prevent the independent rotation of the plate I4 while permitting the shifting of the plate M.

In the operation of this improved device when the sleeve 1 carrying the cams or wedges'4 slides toward the fingers ll], the tapered faces 5 acting as wedges slide over the fingers and force the free ends to swing inwardly on their pivots ll. As the fingers swing inwardly the thrust portions l3 force back the plate [4 carrying with it the nut 22 and collet or chuck operating tube 2|, which in turn draws the collet in and closes it upon the work or stock rod thus clamping the work or stock rod in position to be acted upon by the tools carried by the usual tool slides. When the tool operations are complete sleeve I is shifted in the opposite direction releasing the cams 4 from the fingers If! whereby centrifugal force during the rotation of the work spindles at high speed opens or spreads the fingers thereby releasing the pressure on the plate I and due to the spring action of the collet the plate slides forward thus releasing the collet from the work to be automatically fed through to its next position.

It is to be understood that, by describing in detail herein any particular form, structure or arrangement, it is not intended to limit the invention beyond the terms of the several claims or the requirements of the prior art.

Having thus explaiined the nature of my said invention and described a way of constructing and using the same, although without attempting to set forth all of the forms in which it may be made, or all of the modes of its use, I claim:

1. A finger holder for a rotary spindle carrying a chuck or collet and comprising a body, a slidable sleeve, swinging fingers carried by the body, and

cam means between the body and sleeve and shiftable by the sleeve to engage the fingers to shift them throughout their entire movement in one direction thereby to close the collet or chuck, said cam means, when shifted in the opposite direction, permitting the full opening of the fingers by centrifugal force during the rotation of the spindle, thereby to permit the chuck or collet to be opened.

2. A finger holder for a rotary spindle carrying a chuck or collet and comprising a body, a 5 slidable sleeve, swinging fingers carried by the body, and cam means keyed to the body and sleeve for rotating the sleeve with the body and shiftable to engage said fingers to shift them throughout their entire movement in one direction thereby to close the collet or chuck, said cam means, when shifted in the opposite direction, permitting the full opening of the fingers by centrifugal force during the rotation of the spindle thereby to permit the chuck or collet to be opened. 1 5

3. A finger holder for a rotary spindle carry ing a chuck or collet and comprising a body, a slidable sleeve, swinging fingers carried by the body, and cam means comprising a plurality of independently supported sliding cams keyed to the body and sleeve for rotating the sleeve with the body and shiftable to engage said fingers to shift them throughout their entire movement in one direction, thereby to close the collet or chuck, said cam means when shifted in the opposite 25 direction permitting the full opening of the fingers by centrifugal force during the rotation of the spindle thereby to permit the chuck or collet to be opened.

4. The combination with a rotary hollow spindle having a collet or chuck operating sleeve therein, of a finger holder carried by the spindle comprising a shiftable plate connected with the sleeve, a slotted body carried by and rotatable with the spindle, a pair of pivoted fingers carried by and within the slots of said body and in position to exert a thrust against said plate to slide the sleeve within the spindle and shiftable in one direction by centrifugal force, a pair of sliding wedge cams carried by and within the slots of said body and in position to externally engage said fingers to shift them in the opposite direction and a sliding sleeve encircling said body for shifting said cams in the opposite direction.

5. The combination with a rotary hollow spindle having a collet or chuck operating sleeve therein, of a finger holder carried by the spindle comprising a shiftable plate connected with the sleeve, a slotted body carried by and rotatable with the spindle, a pair of pivoted fingers carried by and within the slots of said body and in position to exert a thrust against said plate to slide the sleeve within the spindle and shiftable in one direction by centrifugal force, a pair of sliding wedge cams carried by and within the slots of said body and in position to externally engage said fingers to shift them in the opposite direction and a sliding sleeve encircling said body for shifting said cams in the opposite direction, said last sleeve having slots for the reception of 50 said cams whereby the body and sleeve are keyed together for rotation.

6. The combination with a rotary hollow spindle having a collet or chuck operating sleeve therein, of a finger holder carried by the spindle 5 comprising a shiftable plate connected with the sleeve and having a transverse slot across its inner face, a slotted body carried by and rotatable with the spindle and having a tongued end projecting into the transverse slot of the plate 7 whereby the plate is guided on the body, a pair of pivoted fingers carried by and within the slots of said body and in position to exert a thrust against said plate to slide the sleeve within the spindle and shiftable in one direction by cen- 15 trifugal force, a pair of sliding wedge cams carried by and within the slots of said body and in position to externally engage said fingers to shift them in the opposite direction and a sliding sleeve encircling said body for shifting said cams in the opposite direction.

7. The combination with a rotary hollow spindle having a collet or chuck operating sleeve therein, of a finger holder carried by the spindle comprising a shiftable plate connected with the sleeve and having a transverse slot across its inner face, a slotted body carried by and rotatable with the spindle and having a tongued end projecting into the transverse slot of the plate whereby the plate is guided on the body, a pair of pivoted fingers carried by and within the slots of said body and in position to exert a thrust against said plate to slide the sleeve within the spindle and shiftable in one direction by centrifugal force, and having its pivotal points within the tongued body, a pair of sliding wedge cams carried by and within the slots of said body and in position to externally engage said fingers to shift them in the opposite direction and a sliding sleeve encircling said body for shifting said cams in the opposite direction, said last sleeve having slots for the reception of said cams whereby the body and sleeve are keyed together for rotation.

whereby the shiftable means is rotatable with the body but slidable relative thereto and is both rotatable and slidable with the sleeve.

9. A finger holder comprising a body, a sliding sleeve encircling the body, a shiftable operating finger carried by the body, and shiftable means between the sleeve and body for engaging the finger to shift and release it, said body having a slot for the reception of a part of said shiftable means whereby it is rotatable with the body and slidable relative thereto and said sleeve also having a slot for the reception of a part of said shiftable means whereby it is rotatable with the sleeve and said shiftable means also having a transverse recess for the reception of a part of 25 the sleeve whereby it is slidable with the sleeve.

CHARLES Q. GAREY. 

